Let's bring in ABC's David Curley and ABC news contributor colonel Steve ganyard, an aviation accident investigator. Both have been on the story from the start. Thanks for joining us. Start with you, Steve. You look at the vast search area and it reminds me how small the search area was for air France. They had debris within five days, and then it took two years. But this area is so huge. It is. The good news is, if you remember earlier in the week, we were looking at 2 million square miles. So the so-called good news is we're down to a search area the size of the state of Texas. You reference the air France mishap because of the similarities. In that mishap, probably looking at something the size of Connecticut. Still a daunting, daunting search area. And if we find the debris, if that is actually debris from the airplane, it doesn't mean we're going do find the airplane. That's right. I think we ought to think of this as two separate search areas. We're looking for things on top of the water that still may be floating. But where the airplane went into the water is some 350 to 700 miles away. Even if we do find this debris, I don't think it's going to help us find the airplane that could be 700 miles away at the bottom of the ocean. Because of the currents and the place the plane went in. David, but if they do find debris, if they just find the debris from the airplane, can that give us any clues? Big clues. We don't have many clues. If you pick up a piece of wreckage, you can tell whether or not there was a fire. The forensic folks can tell how it hit the water. Straight nose down, skip along. There are things they can tell from this. And a lot of the debris inside the fuselage and from the aircraft will have serial Numbers on it to prove it came from the 777. And remind us if the black box is found what we can learn from that. Two black boxes. One is a cockpit voice recorder. It recycles every two hours. It was so long, we might hear sounds but no voices. And the flight recorder, about 11 years old. Could have thousands of data points, hundreds or maybe a thousand or more. And what the pilots inputted into the system, what the plane was doing, how the fuel burn was going. It would be a godsend if we could find the flight data recorder. We are entering the third week. We have talked to you almost every day. Today as you sit here, what do you think brought the plane down? There's not enough evidence. There's nothing that's happened to suggest anything different in some of the theories we have been talking about for almost two weeks. Everybody believes the marginal evidence suggests there was a deliberate act by somebody in that cockpit. Beyond that, we really don't know anything more and we need more facts, and time is running out. I was thinking, the world is riveted by this mystery. We have all gotten on airplanes, surrendered ourselves to two strangers in a cockpit or watched loves one go out and do the same. Is there something from what we haven't learned. The transponder shut off, haven't found the black box. Do you think there's anything that will change going forward? Whether we find it or not? It's a matter of will. There were suggestions after the France crash to prevent this from happening again. None were implemented. Maybe with a second tragedy, something will happen. It's not the technology, it's just a matter of who pays for it. Thanks. And what we find. You have been so great on the story. Now to breaking news from Ukraine, Russian forces opening

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